Method of assembling circuitry



Dec. 13, 1966 F. J. TANCK METHOD OF ASSEMBLING CIRCUITRY Filed March 26,1963 Fig. 2

FRANK J. TA/VCK INVENTOR. fiZnw/M ATTORNEYS United States Patent3,290,757 METHOD OF ASSEMBLING CIRCUITRY Frank J. Tanck, Rochester,N.Y., assignor to Eastman Kodak Company, Rochester, N.Y., a corporationof New Jersey Filed Mar. 26, 1963, Ser. No. 268,013 1 Claim. (Cl.29155.5)

This invention relates to an electric conductor assembly arrangementand, more particularly, to an apparatus and method for assembling aplurality of insulated electric conductor elements having apredetermined critical spacing.

In the art of electric conductors involving support of adjacentco-operating conductors which are respectively insulated, there are manycomplex arrangements for assembly which result in undue time and motionin accomplishing a complete assembly. A most troublesome problem is toassemble several closely spaced conductors having critical spacingrelationships, particularly if the parts are small or difiicult to placein a particular location.

Therefore, an object of my invention is to provide a simple and reliableelectric conductor assembly arrangement.

A more specific object is to provide an arrangement for assembling aplurality of closely spaced conductors.

In accordance with one embodiment of my invention, a plurality ofseverable electric conductors are formed from a single metal conductorunit to have small, high resistance support bridge connections betweenthe elements thereof. This composite electric conductor unit is thensecured to an insulated member by gluing, soldering, riveting, and thelike, whereupon the high resistance bridge couplings are removed bycoupling adjacent conductor elements in series with a high currentsource to vaporize the high resistance bridge couplings in the manner inwhich fuses are blown.

The subject matter which is regarded as my invention is particularlypointed out and distinctly claimed in the concluding portion of thisspecification. The invention, however, as to its organization andoperation together with further objects and advantages thereof, willbest be understood by reference to the following description taken inconnection with the accompanying drawing in which:

FIG. 1 is a perspective view of electric conductor elements partiallyassembled in accordance with the present invention; and

FIG. 2 is a detail plan view of a portion of the assembly shown in FIG.1.

Referring now to the drawing wherein like numbers refer to similarparts, I have shown in FIG. 1 conductive elements 10, 11, 12, 13, 14 and15. As is apparent from FIG. 1, the elements 10, 11, and 12 are formedfrom a single conductive strip of brass or the like to have small, highresistance bridges 17, 18, 19 and 20 of the same material therebetween.Such a construction may be fabricated by hand operations, but is oftenformed by a multistation punch press, which, by way of example, punchesout unwanted portions, forms some portions, bends other portions, trimsdetails, etc. The bridges 17-20, although of the same material as theconductive members -12, are relatively high resistance because of theirsmall crosssectional area. Also, these bridges are curved slightly toraise them above an insulating platform 22 to which the conductivemembers 10-12 are secured. The particular platform 22 shown defines anaperture 23 through which wires, levers and the like may be inserted orfluids and the like may be transported.

The conductive members 13-15 (FIG. 1) have already been separated byvaporization of bridges 26 and 27 (FIG. 2). Prior to vaporizing thesebridges, the conductors 13-15 were a single conductor, as shown in FIG.2

3,290,757 Patented Dec. 13, 1966 and were secured by glue or the like toan insulating plate 28. The plate 28 is secured to the platform 22 as anintegral part thereof with a step therebetween having a riser 29 toprovide additional support to the conductive :members 10-12.

The original separation of the bridges 17-20 and 26-27 from the flat,smooth supporting insulator prevents the building up of substantial heatand vapor pressure which might tend to loosen the conductors from thesupport. This problem is further alleviated by the provision of recesses31 and 32 in the insulating plate 28 in the region immediately adjacentto the bridges 26 and 27, which are to be vaporized. The recesses 31 and32, in combination with raising the bridges 26 and 27, prevent charringof the insulation, which might result in a leak current flow, andfurther prevent damaging deposition of any conducting vapor resultingfrom the vaporization step. There are, of course, insulative materialssuch as polytetrafluoroethylene, which are not subject to charring ordeposition considerations. The use of such materials would reduce oreliminate the need for such recesses. However, we prefer to use recesses31 and 32 and equivalent recesses 33 in the region of the bridge 17-20.As an alternative,

the conductive portions adjacent to the bridges 17-20 could be raisedsubstantially from the insulating platform 22.

It should also be noted from FIGS. 1 and 2 that another bridge 34 isprovided in the central portion of the conductor 15 whereby theconductor 15 is substantially identical to the conductors 13 and 14prior to the bridge 26 being removed. Moreover, these conductors 13-15are relatively small and, therefore, somewhat difiicult to positionindividually on a smooth surface of the type presented by the insulatingplate 28. The assembling of the small conductors 13-15 as a single unitresults in substantial labor savings. This is particularly true if theaccess to the final assembly is substantially covered by other equipment(not illustrated) as is often the case in practice.

In FIG. 1 the conductive member 10 is provided with a portion 35 whichis supported by the riser 29. This portion has there-on a contact button36 suitable for engaging a portion of a battery 38 (shown in phantom).The conductor 11 is provided with a similar portion 39 having two suchraised buttons 40 and 41 to engage batteries 42 and 43 (in phantom), andthe conductor 12 is provided with a similar portion 44 having a button45 to engage a battery 46. Further support of the batteries 38, 42, 43and 46 is provided by the plate 28 and by the conductors 13-15, whichare provided with resilient fingers 48, 49, 50 and 51 to engage theother ends of the batteries.

The assembly thus described is arranged to energize a load means such asa lamp 53 coupled in circuit with the conductors. In this instance, thelamp 53 is coupled serially between the conductors 13 and 14 so thatafter the conductors 10-12 are isolated by vaporization of the bridges17-20, the lamp 53 may be energized by all four batteries whenever adisc contactor 54 (shown in phantom) is rotated to have a conductiveshoe 56 thereof engage a pair of contact arms 57 and 58 of theconductive members 10 and 12 respectively. Similarly, the lamp 53 may beenergized by only two of the batteries (43 and 46) by coupling ofcontactors 60 and 61 by a contact arrangement, not illustrated.

In order that the contact arms 57-58 and the contactors 60-61 may bereliably coupled by their respective operators, the relative spacing ofthe conductive members 10-12 is critical. Also, the spacing of thebattery contact buttons 36, 40, 41 and 45 must be within reasonablelimitations. As is often the case, the relative spacing of these partsis more critical than the absolute location. For instance, under certainenvironmental conditions, A" spacing between parts 10, 11 and 1-2 isacceptable, but is assembly provides assembly tolerances of less thanObviously, jigs and fixtures may be simplified using my invention aswell as reducing the assemblers time and motion.

Referring now to FIG. 2, the bridges 26 and 27 may be vaporized bycoupling one terminal of a high current source 64 to the conductor 14 bymeans of a probe 65.

The other terminal of the high current source 64 is connected through aswitch 66 to the conductors 13 and 15 through probes 68 and 69. In theparticular construction illustrated, care must be maintained to positionthe probe 68 in the region of the finger 49 so that the bridge 34 is notvaporized, as these two fingers 48 and 49 must remain electricallycoupled to accomplished the complete series array of the batteries 38,42, 43 and 46, as illustrated in FIG. 1.

In FIG. 1, the high current source 64 (or a similar source) is couplableby the switch 66 to electrodes 65', 68 and 69' to accomplishvaporization of the bridges 17-20. Once separation of the conductors -12is accomplished, the disc contactor 54 may be rotated in a programmedmanner by turning of its shaft (not shown),

which supports the disc contactor 54 in a predetermined engaging spacingrelative to the contactors 57 ad 58 by means of a bearing aperture 71 inthe platform 22. A similar bearing aperture 72 is provided for thecontact used to engage the contactors 60 and 61.

While I have shown and described particular embodiments of the presentinvention, other modifications may occur to those skilled in this art.For instance, if only two conductors are to be assembled simultaneously,only two probes (68 and 69) need be used. On the other hand, if manyelements are assembled as a unit and then separated by vaporization,there will be more probes arranged to couple alternate elements toopposite sides of the high current source. Similarly, several switches(66) may be used to accomplish vaporization in a sequential mannerwheresupport of one element is accomplished from several adjacent andcoupled-together elements. Also, the conductive members 10-12 could becoupled by bridges to locate the conductive members 13-15. But

usually the economics of assembly would not fully justify thesubstantial increase of scrap of such an arrangement. Furthermore, myinvention may be advantageously used to assemble a single element inrelatively inaccessible locations whereupon once the element is secured,an integral handle may be severed therefrom by my vaporizationtechnique. I intend, therefore, to have the appended claim cover allmodifications which fall within the true spirit and scope of myinvention.

I claim: A method of producing an electrical conductor assemblyarrangement having an insulating base and at least two shaped conductiveelements fixed to the insulating base in a critical predeterminedspacing relationship relative to each other, comprising the steps of:

forming the conductive elements from a single strip of conductivematerial with at least one integral high resistance bridge ofsubstantially reduced cross section integrally joining the elements as asingle piece;

shaping the elements to the desired shape and bending the bridge to forma curved bridge raised relative to the portions of the elements adjacentthe bridge and to establish and maintain the predetermined spacingbetween the elements; forming the insulating base with surface areas forsecuring the elements thereto and forming a recess in the insulatingbase between the surface areas;

securing the elements directly to the surface areas of the insulatingbase with the curved bridge directly over the recess and spaced from theinsulating base by the amount of raising and the amount of recess;

and coupling the elements in series with a high current electricalsource to vaporize the high resistance bridge and separate the joinedelements without damaging the insulating base, or loosening or affectingthe spacing between the elements secured to the base.

WHITM'ORE A. WILTZ, R. W. CHURCH,

Assistant Examiners.

